# Patient-note annotation exercise

Compare three treatments of one invented note. The worksheet illustrates review decisions, not a legal determination about a real dataset.

Entirely synthetic patient, events and identifiers. No expert determination or product test has been performed.

Source: https://aona.ai/resources/guides/hipaa-de-identification-ai-patient-notes/
Sources checked: 2026-09-21

## Masking is one transformation

### Invented original

Mara Example, MRN TEST-4821, age 93, attended on 14 March 2026.

Note: The worksheet also includes a distinctive occupation.

### Name-only masking

Patient A, age 93, attended on 14 March 2026.

Note: Date and age details remain. This is not de-identification.

### Reduced-detail example

An adult aged 90 or older discussed a routine follow-up in 2026.

Note: Teaching example only. Apply the full chosen method to a real record.

| Item in invented note | Why review it | Illustrative treatment |
| --- | --- | --- |
| Mara Example; MRN TEST-4821 | Name and medical-record identifier. | Remove both, rather than replacing only the visible name. |
| Seen on 14 March 2026 | Date directly related to an individual. | Retain 2026 only for a Safe Harbor review. |
| Age 93 | Age above 89. | Use the category age 90 or older. |
| Only harbour master in a small town | Distinctive context may identify the person. | Omit occupation and locality where unnecessary; assess remaining context. |
| Patient A attended on 14 March, age 93 | Masking retains multiple identifying clues. | Do not label this version de-identified. |
| Older adult discussed a routine follow-up | More general wording loses clinical detail. | Check task utility and the complete chosen method before any real release. |

## Review checklist

- [ ] Record the chosen legal method
  Distinguish Safe Harbor review, documented Expert Determination and ordinary masking.
- [ ] Review the complete output
  Apply identifier and contextual checks to free text, all file content and relevant metadata.
- [ ] Keep the release conditions
  Record the recipient, remaining information and reason the selected method is satisfied; do not invent reviewer sign-off.

## Included example files

- patient-note-deidentification-exercise.md
- patient-note-deidentification-exercise.csv

## Source references

- HHS: Methods for de-identification of PHI: https://www.hhs.gov/hipaa/for-professionals/special-topics/de-identification/index.html (2026-09-21)

Use the worksheet within the relevant legal, contractual and technical scope. It is not a certification or a record of an installed-product test.